Equal-expenditure purchases: A person spends ₹36 at each of five markets, where prices per orange are ₹1.00, ₹1.50, ₹1.80, ₹2.00, and ₹2.25. Find the average price per orange across all oranges bought.

Introduction / Context:
When spending equal amounts at different prices, the number of items purchased varies inversely with price. The overall average price equals (total spent) / (total items), which simplifies using reciprocals of the prices (a harmonic-mean style setup weighted by equal expenditure).

Given Data / Assumptions:

• Spend per market = ₹36 (five markets)
• Prices: ₹1.00, ₹1.50, ₹1.80, ₹2.00, ₹2.25 per orange

Concept / Approach:
Total oranges = Σ(36 / price). Total spend = 5 * 36. Average price = (total spend) / (total oranges) = 5 / Σ(1 / price).

Step-by-Step Solution:

Verification / Alternative check:
Compute total oranges explicitly: 36, 24, 20, 18, 16 → total 114 oranges for ₹180 → 180/114 = ₹1.5789..., same result.

Why Other Options Are Wrong:

• ₹1.91, ₹2.00, ₹1.80, ₹1.70: do not equal 30/19 to two decimal places.

Common Pitfalls:
Averaging prices directly (arithmetic mean) without accounting for different quantities obtained at each price due to equal spending.

Final Answer:
₹ 1.58